how do I get off my plateau?

@1
"how do I get off my plateau?"
++ Key is to analyse your lost games and learn from your mistakes.
"I take to long to move" ++ Thinking long is good. What is your problem?
"casual blitz games" ++ 'Blitz kills your ideas' - Fischer
"I have theory for the openings" ++ Not useful
"I always get sidetracked by a weird line I'm not used to"
++ When you see something unusual, then think.
"when I'm in an opening I didn't know, I usually play it accurately" ++ Good.
"I find myself in the mindset that I'm losing because of my confusion." ++ No need to.
"This leads me to take draws in games where I'm winning" ++ That is stupid.
"I didn't know how to win from them" ++ Study endgames.
I overthink to a good tip is to play at sort of a tempo like think every 10-20 sec and in blitz every couple of sec and use your time only for key moves (I don't use my time but I should)
For over thinking classical esc music any old one or maybe classical esc video game music civ 6 like ftl pvz etc but I'm not sure what he rules are for music during the otb turnements
@6
"I'm not sure what he rules are for music during the otb turnements"
++ Forbidden
'11.3.2 During a game, a player is forbidden to have any electronic device not specifically approved by the arbiter in the playing venue.' https://handbook.fide.com/chapter/E012023
Hello, all!
I have been stuck at 1400 USCF for as long as I can remember and even though I'm an active tournament player, it seems I'm hard stuck.
One of my main problems is that I take to long to move and overcomplicate my position in long time control games OTB. I think this overthinking may be affecting my performance drastically as I play like a computer in casual blitz games with my friends. Also, I have theory for the openings I play, but I always get sidetracked by a weird line I'm not used to.
And into my next point, when I'm in an opening I didn't know, I usually play it accurately but I find myself in the mindset that I'm losing because of my confusion. This leads me to take draws in games where I'm winning, and in those situations I didn't know how to win from them
If you can recommend any things that could help me, it would be highly appreciated. (Note: my coach says I play middle and engage like an 1700-1800 ELO, but I just get confused in the opening).
Thank you, Lolimreallybad